What he made of her is not recorded.
As everyone knows, the Duke is not immune to the charms of glamorous women but on this occasion he could be forgiven for being preoccupied. Days later, his name would emerge in explosive court papers making claims – all vehemently denied – about his friendship with convicted US paedophile Jeffrey Epstein.
Arcuri, though, got what she wanted: another big name to drop, another profile-boosting story with which to regale the technology world's movers and shakers.
As the Mail on Sunday today reveals, perhaps the greater significance of her palace outing was that it was, according to her friends, engineered by her close friend, Boris Johnson.
Almost five years on, the Prime Minister faces claims of failing to declare a series of potential conflicts of interest over his friendship with Arcuri during his time as mayor.
She received £126,000 ($245,800) in public money and privileged access to three official overseas trade missions led by Johnson, who was a regular visitor to her flat in Shoreditch, East London. Friends and acquaintances interviewed by the newspaper cast Arcuri as a vivacious, fun-loving young woman who by sheer force of personality bedazzled those she believed could help her achieve her goals.
One man close to her around the time of the Palace event recalled: "She said Boris had helped her get on the guest list. She was very keen to raise investment for her various businesses. She boasted to anyone who would listen that she was going to the palace and afterwards wouldn't shut up about it."
There was a champagne reception and then Cabinet Office Minister Francis Maude made a short speech about making online Government services more user-friendly. One guest described the soiree as a "melting pot of royalty, senior politicians, Government digiterati, and tech start-up folk".
Another friend recalled that the help Arcuri received in getting through the door typified her "symbiotic relationship with Boris", who had significantly boosted his profile in the industry by giving a speech at her firm's first event.
"Jen presented herself as a kind of gateway to Boris," said the friend.
"If you were a tech start-up founder and wanted access to the Mayor's office, everybody knew that you would ask her. New tech companies craved proximity to government at this time. I understand she did make plenty of introductions to Boris' staff. And it worked both ways. The Mayor's office used her for introductions in the technology world.
"She spoke about Boris as though she had his ear and as though he relied upon her for advice and connections and information when it came to technology."
After arriving in London in 2011 and completing an MBA at an international business school, Arcuri set up Innotech, a series of networking summits bringing together young entrepreneurs based around the burgeoning East London Tech City – branded the Silicon Roundabout – with politicians and policy makers.
The friend added: "She was very keen to ingratiate herself with the UK Government and she set about injecting herself into all aspects of Tech City, draping herself in Union flags at events, for instance.
"She enjoyed bragging about Boris. She enjoyed doing that sort of, 'I am taking you into my confidence, you can't tell anyone, not a soul knows, don't breathe a word' kind of thing, except she was doing that with 20 people.
"Once she had brought you into her confidence, she would then start dropping his name into conversation quite regularly, talking as though she was an intimate of his, as in, 'I will have to ask Boris about that.'"
Today, they are on opposite sides of the world – Arcuri lives in California, Johnson is the occupant of 10 Downing St – but their friendship is now the subject of fierce scrutiny.
On Friday, the Prime Minister was referred to the Independent Office for Police Conduct watchdog and could yet face a criminal investigation over whether he gave favourable treatment to Arcuri. The complaint was made to the IOPC because of Johnson's role as Police and Crime Commissioner in London from 2008 to 2016.
The move was criticised yesterday. Environment Secretary Theresa Villiers told BBC Radio 4's Today programme that the matter had been "blown out of all proportion", adding: "The Prime Minister is very clear that proprieties were observed. This seems to be pretty obviously a politically motivated complaint. I do feel this is a distraction and it is people seeking to use the complaints process in a highly political way."
A fortnight before her palace outing, Arcuri was one of 26 delegates chosen to travel alongside Johnson on a taxpayer-funded trade mission to Singapore and Malaysia.
To qualify, delegates had to be able to show that their companies had been trading for at least 12 months. Arcuri was the only one who did not meet the selection criteria.
A London-based fashion designer said she lent Arcuri some clothes for the trip: "Though she had this profile and wouldn't stop talking about the influential people she knew – particularly Boris – I got the feeling her businesses didn't quite match all the buzz. She didn't have much money.
"For example, she didn't have the right outfits to wear for Singapore and I lent her some silky tops."
She added: "We were quite friendly and I remember her persuading me to come to one of her conferences where Boris was speaking. Afterwards, she asked if I wanted to meet him. We went to a room behind the stage. They were very tactile with each other, flirty, and it made me feel a bit uncomfortable, so I left."
At this point, Arcuri was deeply immersed in the boozy Tech City party scene.
"She was omnipresent," said one friend. "But I suspect Boris and City Hall probably overestimated her influence."
Away from parties, she loved to gossip with friends at the Hoxton Hotel and Shoreditch House, a members' club.
A senior figure in the tech industry said: "I don't recall feeling heavily pressured or lobbied by her but I know that other people did. With her outfits and her Boris stories, I found her slightly corny but ultimately she was a fun person to have around."
A former Cabinet Minister recalls Arcuri "seemed to be at every event going" between the summer of 2013 and 2016, adding: "She was ubiquitous. She was everywhere. If there was a gathering about cyber security, she would be there.
"She had no qualms walking up to people – senior people – and really selling herself and having fun. She was a larger than life character.
"I remember her sales pitch. She would say, 'Give me your phone and I will show you how easy it is to hack you'. Of course I never did."
By 2016, Arcuri had met her future husband Matthew Hickey in London and they relocated to the northwest where they ran a new company called Hacker House, which taught people about cyber security and how to hack "ethically".
For eight months, they rented a £1million mansion house in Cheshire where they would run hacking seminars.
One of the hackers employed by Arcuri was activist Lauri Love, who at the time was fighting his extradition to the US for allegedly hacking into the FBI.
Photographs seen by the newspaper show Love in the kitchen sitting opposite Arcuri during one event at the property.
In another image, Arcuri is pulling on a Guy Fawkes mask of the controversial Anonymous hacking group, which has previously launched cyber attacks against governments.
A source said: "She wanted to hide her identity. She was like, 'I look dreadful, I've no makeup on'."
Yet her social media profiles tell a different story. Included are selfies with any number of politicians, among them Michael Gove, Zac Goldsmith and Justine Greening.
A second source who knew Arcuri from that time claimed Johnson visited the house in Cheshire in the spring of 2016.
They said: "She told me, 'Guess who came round the other day, and came back here at some point? Alexander!' I said, 'Well who is Alexander?' And then she told me the proper name [Alexander Boris de Pfeffel Johnson].
"But that was the name she used – 'Alexander the Great'."
Describing Arcuri as a "social climber", he added: "She liked to drop names to leverage people, to get into networks, hustle a bit for funding. I suppose it's what you do if you're an entrepreneur. If anyone has crossed lines, it wasn't Jen so much for trying to weave her way into these circles, it was Boris for blurring the lines a bit more."
The source also said that Arcuri was driving an expensive BMW at the time, adding: "It was all for show – a very American model. If you come from Los Angeles, you have got to look successful to be successful. Fake it 'til you make it."
Arcuri did not respond to requests to comment, but has previously said: "Any grants received by my companies and any trade mission I joined were purely in respect of my role as a legitimate businesswoman."
A Downing St spokesman said: "The Prime Minister, as Mayor of London, did a huge amount of work when selling our capital city around the world, beating the drum for London and the UK.
"Everything was done with propriety and in the normal way."
Buckingham Palace said last night: "The Prince's reception welcomed more than 100 guests."
